Numerous industries require systems to separate liquids of different densities and most separation processes rely on vertical movement of liquids in a large vessel. Most large vessels used for liquid separation are elongated, horizontal and cylindrical in shape. Liquid distribution in the lower portion of a horizontal, cylindrical vessel is normally accomplished using either a perforated pipe-type spreader or a perforated open bottom box-type spreader. Several techniques are typically used to improve liquid distribution along and across the vessel cross-sectional area. These techniques include proper sizing of the flow channels, proper selection of the spreader hole sizes, proper lengths of the spreader pipe, proper dimensions of a box and spreader configuration, and the proper selection of the basic spreader design, such as H-type laterals, T-type laterals, and S-shaped pipe distributors, among others.
The efficiency of a separation process depends to a great extent on the proper distribution of liquids within the separation vessel. Proper distribution is, in turn, largely a function of the kinetic energy of the liquid streams as they are released into the separation vessel. If the liquid released into a separation vessel has a high kinetic energy when discharged from a spreader, the resulting parasitic movement of liquids within the vessel can dramatically reduce the efficiency of separation.
Typically, when liquids are discharged from holes in a spreader in a vessel, the liquid will continue in a straight line until it is deflected by an internal surface, such as the vessel wall. If an unrestricted liquid flow is allowed to continue for a prolonged period of time, it will induce a second or parasitic flow within the vessel which contributes to ineffective liquid distribution within the vessel and reduced efficiency of separation.
An objective of this invention is to provide a system and method of use thereof that achieves more efficient liquid separation by reducing the kinetic energy of liquids distributed within a separation vessel and attenuates the momentum of liquid streams as they are introduced so as to substantially reduce the creation of parasitic flow streams.
For background material relating to this subject, reference may be had to a manual published by National Tank Company entitled "Treater Design Manual" and particularly Section C.400 entitled "Spreaders and Collectors" having been issued on Jul. 1, 1997. Pages C.400 TM-1 through TM-4 of this manual are incorporated herein by reference.